After receiving his law degree in Mexico and completing graduate study at the University of Paris and at the International Law Academy in The Hague, García Robles entered Mexico’s foreign service in 1939 and was a delegate to the 1945 San Francisco Conference, at which the United Nations (UN) was founded. He subsequently worked in the UN Secretariat for several years. As director general in the Mexican Ministry of Foreign Affairs during the late 1950s, García Robles played a central role at the Law of the Sea conferences, which defined the continental shelf for conservation purposes.

While serving as ambassador to Brazil, he first encountered the proposition of excluding nuclear armaments from Latin America, and, after the Cuban Missile Crisis of 1962, he persuaded the Mexican government to support such a policy. His unremitting efforts eventually led to the Treaty of Tlatelolco (1967), which committed 22 nations of Latin America to bar nuclear weapons from their territories. A year later he helped draft the Treaty on the Non-proliferation of Nuclear Weapons. He was appointed permanent representative to the Disarmament Conference in Geneva in 1977. In 1978 he served as chairman of the Mexican delegation to the UN General Assembly’s special session on disarmament. The author of more than a dozen books, García Robles is remembered as one of Mexico’s most distinguished internationalists of the 20th century.